Stanley Kubrick’s 2001: A SPACE ODYSSEY first premiered in the U.S. on April 2, 1968. As the visual masterpiece turns 48 this week, read an essay penned by science writer Isaac Asimov about the film for a 1977 issue of American Film. Science fiction, at least in the world of film, had, ever since the ’30s, established itself as youngster-oriented. It was cops and robbers, good guys and bad guys, white hats and black hats. It was stylized as the youngster-oriented Western. Change the keen-eyed, rangy cowboy on his cayuse, to the keen-eyed rangy astronaut at his controls; the schoolmarm into…